1. Field of the Invention
The present invention relates to a vibrator support structure and to a method of manufacturing the support structure.
2. Description of the Related Art
Up to now, in vibrating gyroscopes, a vibrator support structure provided with a vibrator having a bending vibration mode, support pins for supporting the vibrator, and a substrate on which the vibrator is mounted through the support pins has been adopted. That is, in the vibrator, a pair of piezoelectric substrates oppositely polarized in the thickness direction are joined so as to face each other, and one piezoelectric substrate, on which first and second detector electrodes are formed so as to be separated from each other, and the other piezoelectric substrate, on the entire surface of which a drive electrode is formed, are joined so as to sandwich an intermediate electrode.
Then, the support pins are attached to the first and second detector electrodes at locations corresponding to vibration nodal points and also the support pins are attached to the drive electrode at locations corresponding to vibration nodal points. Furthermore, a substrate connection portion, which is an outer end portion of each support pin, is joined to each pin connection portion provided on the substrate by soldering. Accordingly, the vibrator is mounted on the substrate through the support pins and is supported so as to be able to perform bending vibration (see Japanese Unexamined Patent Application Publication No. 2001-227953, for example).
Moreover, in another vibrator support structure, a substrate connection portion, which is an outer end portion of an L-shaped support pin, is inserted into a through-hole of an attachment part which is not the substrate, and the substrate connection portion of the support pin is fixed to the attachment part by soldering. In this support structure, a separate buffer material is placed between the attachment part and the substrate (see Japanese Unexamined Patent Application Publication No. 6-221854 and Japanese Unexamined Patent Application Publication No. 6-258082, for example).
In the vibrator support structures of the related art, the substrate connection portion of the support pins and the pin connection portion of the substrate are joined by soldering. However, since the solder, which is a metal, is solidified and hardens, vibrations leaking from the vibrator are easily propagated to the substrate through the support pins and a residual stress is easily caused in the support pins. Furthermore, in such a support structure, it becomes easy for impacts applied to the substrate from the outside to be directly propagated to the vibrator through the support pins.
On the other hand, in a vibrator support structure in which an attachment part fixed on a substrate with a buffer material therebetween and a substrate connection portion of a support pin are soldered, there is an advantage in that the vibrations and impacts propagated through the support pin are weakened by the buffer material. However, the fact is that, since it is necessary to place a buffer material between the attachment part and the substrate, the number of parts increases and the structure becomes complicated, and, as a result, this requires additional during the assembling process.
Moreover, as long as a vibrator support structure using soldering is adopted, reflow mounting of a vibrating gyroscope accompanied by the re-melting of solder cannot be avoided. Accordingly, the trouble of changing the balance between parts in the vibrator support structure, that is, damage of support conditions due to the release of residual stress, etc., is likely to occur.